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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.

Sustainable mass handling : Modelling quantities of excavated soil and rock in residential construction projects

Israelsson, Filip January 2014 (has links)
An efficient handling process of aggregates and excavated soil and rock will be of increasing importance in expanding urban regions. The construction of residences, infrastructure and commercial areas generate significant amounts of soil and rock that can be re-used more efficiently as construction material, minimizing transportation and environmental impact. A key element is the implementation of central intermediate storage sites for re-use purposes and cooperation between several construction projects in a region. The evaluation of storage capacities and optimal site locations is in turn dependent on comprehensive knowledge about what quantities of aggregates and excavated soil and rock that will be generated and utilized in the region. The calculation model presented in this thesis provides a way of estimating the amount of excavated soil and rock generated during the construction of new residential areas at an initial stage of the planning process. The excavated volume is expressed as a function of the number of residents and the number of floors in the buildings of the planned area, allowing for an early estimation that may effectively influence the logistical planning of the mass handling process. The simplified calculation model applied to a case study of the existing residential area Annedal in Stockholm produces an estimated amount of 577 500 ton excavated soil and rock, approximately 3.8 % lower than the reference value of 600 000 ton. Regional storage sites are advantageous as different construction projects generate and utilize different types of soil, rock and aggregates, resulting in a higher possible re-use share than in individual projects. When regarding the energy usage in transportation, it is shown that intermediate storage sites located within 10 km of the construction site may allow for more than 15 % energy reduction if re-using 25 % of the excavated amount of soil and rock. A distance of 5 km may yield more than 20 % reduction of transportation energy for the same share of re-use.

Exposure conditions affecting leaching of geogenic contaminants from excavated soils and rocks / 掘削土壌・岩石に含まれる自然由来重金属等の溶出挙動に及ぼす曝露条件の影響

Tang, Jiajie 25 September 2023 (has links)
京都大学 / 新制・課程博士 / 博士(地球環境学) / 甲第24955号 / 地環博第246号 / 新制||地環||49(附属図書館) / 京都大学大学院地球環境学舎環境マネジメント専攻 / (主査)教授 勝見 武, 准教授 高井 敦史, 教授 越後 信哉 / 学位規則第4条第1項該当 / Doctor of Global Environmental Studies / Kyoto University / DFAM

Archaeological manifestations of rank and status : the wooden chamber tombs in the Mid-­Yangzi Region (206 B.C. - A.D. 25)

Liu, Yan January 2015 (has links)
This thesis is centered on the roles of wooden chamber tombs in defining, negotiating and reinforcing status and identity of their owners in early imperial China. The archaeological materials under discussion are wooden chamber burials in the mid-Yangzi region, including the modern provinces of Hubei, Hunan, Sichuan and north Anhui. The first reason why I have chosen this area is because these tombs are well-preserved and provide excellent examples to examine the different material expressions of rank and status at each rank in mortuary contexts. They are complemented by some extensive contemporary texts written on bamboo strips recently discovered in the same general area. The waterlogged burial environment in the mid-Yangzi region allows organic materials, such as textiles, lacquers and bamboo manuscripts, to survive while in other regions, such as the Central Plain, they often perished. Secondly, these tombs are also of a traditional form—constructed as a wooden chamber dug into a vertical pit, and can therefore be considered in relation to earlier Zhou practices. Wooden chamber tombs started to flourish from the eleventh century and became more elaborate from the sixth to the first century B.C. From the first century onward, such a burial type still prevailed in the mid-Yangzi region, while they were replaced by horizontal tombs built with bricks or stones in other areas. Many scholars have, therefore, regarded the prevailing timber structure in the area as a cultural continuity from Zhou system. They interpret them in terms of funeral regulations, especially linking them to archaic ranks and ritual norms drawn from transmitted texts. However, many of these texts that archaeologists consult and cite were written long after the burials and sites were constructed and used. These later texts were modified and passed through many editorial hands over the centuries, and there are considerable inconsistencies between different textual sources. Therefore the second reason why I have chosen this area is because it provides data demonstrating that the text-centered assumptions with respect to archaeological material do not contribute to a better understanding of social relationships in early Han society. Thirdly, there is a strong connection with local Chu tombs. The Jianghan Plain was the heartland of the Chu state before the Qin unification. The tomb construction of the Chu state incorporates a striking preference for timber structures. The timber structure tombs grew more widespread and dominant in this area during the early Han dynasty. In using multiple burial chambers and nested coffins, the local Han elites in the mid-Yangzi region seem to have followed the Chu mortuary practice, as well as in burying a large number of lacquers and bamboo manuscripts. The abundant material evidence of Chu tombs in the area sheds light on understanding of changes in funerary beliefs, showing that the tombs were arranged to meet specific needs of tomb owners. Rather than simply seeing a wooden chamber burial as a passive reflection of written regulation, I consider it as a medium for conveying the different thoughts of its owner and their associates. The material evidence manifested the status and identities of the deceased in concrete physical form. The burial assemblages belong to carefully planned contexts, and serve to constitute idealized social relations, rather than necessarily mirroring day to day reality. As such, burial evidence not only exhibited a part of the biography of the dead, but also expressed identity and socio-political claims of the living. This thesis will show that rank is not the only and major determinant, but is accompanied or outperformed by status and identity. The period covered by this thesis is the initial stage of early imperial China. The Western Han Empire (206 B.C.--A.D. 25) is traditionally regarded as a period when a unified social, political, and ideological framework was initially established. In 202 B.C., Liu Bang (256--195 B.C.) from the former Chu state in eastern China, defeated Xiang Yu (232--202 B.C.) and set up the Western Han imperial court, with its capital in Chang'an (modern Xi'an, Shaanxi province). The Han Empire was briefly interrupted by the Xin Dynasty (A.D. 9--23), established by Wang Mang (45 B.C.--A.D.23), a Confucian official from the Liu family. This interregnum divides the Han dynasty into two periods: the Western Han (206 B.C.--A.D.9) and the Eastern Han (A.D.25--220).

Exploring Networking Barriers for Excavated Soil Management : A case study in the construction industry / En studie av nätverksbarriärer för utgrävdjordhantering : En fallstudie inom byggindustrin

Flodell, Tilda, Aronsson, Nathalie January 2018 (has links)
The construction industry is today one of the greatest consumer of natural resources, and considering the current construction rate, the resource efficiency are to be a challenge. The complexity and uniqueness of the industry create barriers for managing resources efficiently. Construction entails excavation of soil, and from a resource perspective, the excavated soil can be managed more efficiently. The purpose of the study is to examine the network of excavated soil management and how different actors and their roles are intertwined with each other and how they are related to environmental aspects in construction projects. A qualitative case study with a systematic combining approach has been conducted, where semi-structured interviews, observations and secondary documentations were used to collect data. The collected data were further analysed using the ARA-model and the iron triangle. The results generated five main networking barriers for managing the excavated soil more efficiently; communication, co-operation and willingness to compromise/collaborate, unified vision, commitment and structure. However, the analysis resulted in two concluding barriers with the most substantial impact on the excavated soil management. First, the public procurement act which limits the opportunities for early involvement of the contractors, and second, the lack of unified vision regarding the responsibility of the excavated soil. Further, commitment among all actors is required for a joint long-term management. The findings are specific to the case, due to the complexity of the industry. Further research is required to make the results more generalizable.

Hantering av schaktmassor ianläggningsprojekt- Eftersträvan att uppnå massbalans i projekteringsskedet / Handling of Excavated Masses in Construction Projects- The pursuit of achieving mass balance in the projecting stage

Erhardsson, David, Götvall, Stina January 2021 (has links)
Anläggningsbranschen står för stora utsläpp av växthusgaser och att uppnå klimatmål är enutmaning. Genom massbalans, som innebär att återanvända schaktmassor till den fyllningsom är aktuell i största möjliga mån, kan anläggningsbranschen ta sitt ansvar för minskadklimatpåverkan. Massbalans är något som eftersträvas inom anläggningsprojekt för att få enlägre kostnad och tidsbesparing i projektet. Idag klassificeras inte vägbyggnation juridisktsom produktionsprocess vilket skapar ett problem. Produktion ger restprodukter som i sin turkan användas till andra ändamål men denna möjlighet finns inte i anläggningsbranschen ominte syftet för återanvändandet av schaktmassorna fastslagits från början.Rapportens syfte är att tydliggöra vad som gäller vid hantering av schaktmassor, utifrån deförordningar som finns, för att leda fram till hur schaktmassor som avfall ska hanteras vidprojektering inom anläggning. Rapporten avgränsar till projektering med inriktning mot vägoch järnväg och kommer inte att hantera problemen under produktionen efterprojekteringsstadiet. Genom litteraturstudier och intervjuer hämtas information till arbetet.Naturvårdsverket säger att schaktmassor inte behöver bli betraktat som ett avfall om det gåratt hitta ett användningsområde inom samma projekt i tidigt skede med rimlig förutsättningoch tid. Om syfte för återanvändandet av schaktmassorna i tidigt skede saknas bedöms desom avfall och då blir all hantering av schaktmassorna under någon form av anmälnings- ochtillståndsplikt. Det råder stor ovisshet kring tillämpning av lagstiftning vilket leder tillsvårigheter i att förutse vilket beslut tillsynsmyndigheten fastställer kring hur schaktmassornafår hanteras.Länsstyrelsen har nyligen slagit fast att byggnation av en väg inte är en produktionsprocess,vilket gör att schaktmassor inte kan klassificeras som en biprodukt och återanvändning avschaktmassor försvåras. Därmed blir även massbalans svårt att uppnå på grund avlagstiftning och definitioner kring uppschaktade jord- och bergmassor.Slutsatsen är att det juridiska försvårar möjligheten att uppnå massbalans. Somlagstiftningen tillämpas och tolkas i dagsläget försvåras och i vissa fall omöjliggörs arbetet förprojektörer och entreprenörer att uppnå massbalans i samtliga projekt. Enklare ocheffektivare tillvägagångssätt kring syftet med schaktmassorna i anläggningsprojekt skulle gestörre möjligheter för återanvändning. / The construction industry is responsible for major greenhouse gas emissions and to achievethe climate goals is a challenge. By working with a balance of masses, which means reusingexcavated masses for the filling that is relevant as far as possible, the construction industrycan take their responsibility of minimizing the climate impact. Balance of masses issomething that is sought within construction projects to get a lower cost and time saving inthe project. Today, road construction is not legally classified as production which creates aproblem. Production produces residual products which in turn can be used for otherpurposes, but this possibility does not exist in the construction industry unless the purposefor the reuse of the excavated masses has been established from the beginning.The purpose of the report is to clarify what applies when handling excavated masses basedon the existing regulations, in order to guide how excavated masses as waste are to behandled when designing in the construction industry. The report is limited to projecting withfocus on roads and railways and will not deal with the problems in production after theprojecting stage. Information to the report is obtained through literature studies andinterviews.The Swedish Environmental Protection Agency tells that excavated masses do not need tobe considered as waste, if it is possible to find an area of use within the same project at anearly stage with a reasonable condition and time. If there is no purpose for the reuse of theexcavated masses at an early stage, excavated masses are assessed as waste and then allhandling of the excavated masses becomes subject to some condition of notification andpermit requirement. There is large uncertainty about the application of legislation, whichleads to difficulties in predicting which decision the supervisory authority determinesregarding how the excavated masses may be handled.The County Administrative Board has recently stated that the construction of a road is not aproduction process, which means that excavated masses cannot be classified as a byproductwhich makes reuse of excavated masses more difficult. Which makes balance ofmasses difficult to achieve due to definitions and regulations regarding excavated soil androck masses.The conclusion is that the legal makes it difficult to achieve mass balance. As the legislationis applied and interpreted at present, it is made more difficult and in some cases impossiblefor project designers and contractors to achieve mass balance in all projects. Simpler andmore efficient approaches to the purpose of the excavated masses in construction projectswould provide greater opportunities for reuse.

Återanvändning av schaktmassor ur ett hållbarhetsperspektiv för entreprenadföretag / Recycling of excavated soil in a sustainability perspective for construction companies

Fransson, Theodor, Callenryd, Jakob January 2022 (has links)
Regardless of the project within the construction industry there is a high probability that the soil needs preparation, this is often done through excavation. The outcome will likely be a large amount of soil, if these masses can’t be used within the project, they will in most cases be transported to a landfill and be classified as waste. The more transports to landfills and the longer the trip the more greenhouse gases will be produced. Instead, the transport of lower quality masses could go to a recycling facility for treatment as the landfill is not environmentally sustainable. The study is based on a qualitative method, where data is collected using semi-structured interviews. In order to obtain a high content validity and concept validity, the questions in the interviews must be designed from the questions and concepts used in the questions are correctly defining and operationalized. Reliability is obtained by having both authors participate in interviews and that the interviews are recorded audio. Bureaucratic obstacles, uncertainty, untested methods, unclear guidance, laws and requirements mean that many trample on the same place even though the will to work more sustainably exists, these are conclusions made by the collected empirical data. The study resulted in all actors interviewed in this report wanting the recycling and reuse of excavated masses to increase to benefit the environment. The path to that goal looks different for those involved, which is also often the reason why there is not more recycling than what is being recycled today. The implication of the result is that many solutions to these problems lie with the authorities that need to create an economic advantage to recycle compared to driving excavated soil to landfills, that is not sustainable in the long run. Another solution is to reduce processing times for permits and increase permitted storage times. The limitation of work in the interviews is that only one person from each party has been interviewed except for Holst Entreprenad AB, this does not give the entire organization a broad point of view. / Oavsett byggnation inom byggbranschen kommer marken med stor sannolikhet förberedas, detta sker oftast genom schaktning. Resultatet av schaktningen blir en större mängd massor, om dessa inte återanvänds direkt i projektet transporteras de i vissa fall till deponi där de tippas på hög och kommer att klassas som avfall. Desto fler transporter som går till deponi och desto längre sträckan är desto mer ökar koldioxidutsläppen. I stället för att köra sämre massor till deponi skulle transporterna gå till en återvinningsanläggning för behandling då deponi inte är miljömässigt hållbart i längden. Studien baseras på kvalitativ metod, där data samlas in med hjälp av semistrukturerade intervjuer. För att få en hög innehållsvaliditet samt begreppsvaliditet ska frågorna i intervjuerna utformas från frågeställningarna och begrepp som används i frågorna är korrekt definierande samt operationaliserade. Reliabilitet erhålls då båda författarna deltar i intervjuer samt att intervjuerna spelas in. Byråkratiska hinder, osäkerhet, obeprövade metoder, otydlig vägledning samt lagar och krav gör att många trampar på samma ställe även fast viljan att jobba mer hållbart finns. Studien resulterade i att samtliga aktörer som intervjuades i denna rapport vill att återvinningen och återanvändningen av schaktmassor ska öka för att gynna miljön. Vägen till det målet ser olika ut för de inblandade vilket också ofta är anledningen till att det inte återvinns mer än vad det görs idag. Innebörden av resultatet är att många av lösningarna på dessa problem ligger hos myndigheter som behöver skapa en ekonomisk fördel att återvinna jämfört med att köra uppgrävda massor till deponi som inte är hållbart i längden. Det som också skulle öka återanvändningen av schaktmassor är om handläggningstider för tillstånd förkortades och tillåtna upplagstider förlängdes. Arbetes begränsning i intervjuerna är att endast en person från respektive part har intervjuats med undantag från Holst Entreprenad AB, detta ger inte hela organisationens breda synpunkt.

Vägen fram för schaktmassor : En studie inom transporter av schaktmassor och dess koldioxidutsläpp

Stare, Filip, Holm, Axel January 2020 (has links)
According to the Swedish Government, Sweden's goal is to not have any net greenhouse gas emissions by the year 2045. Sweden has come a long way on many levels with its high environmental ambitions, but one sector that is falling behind is the transports with heavy trucks. In 2018, the carbon dioxide emissions were projected to increase by 12 percent compared to 1990. Cities are densified and are expanding, with landfills and recycling facilities moving further and further away, resulting in an increasing quantity of transports of excavated soils and longer traveling distances. This is something that needs to be addressed.This report is written with the aim of investigating whether it is possible to reduce carbon dioxide emissions generated by the transportation of excavated soils from construction projects in the Stockholm region. In addition, this report aims to shed light on the problems surrounding the handling of excavated soils that exists today and provide inspiration for ways to reduce emissions within the construction industry.Five construction projects have been examined regarding the amount of excavated soil and where this soil has been transported. Calculations of carbon dioxide emissions have been made and compared with an optimized alternative in the form of a Mass Logistics Centre.It has been found that the greatest factor for the emissions produced by the transports are not the transports themselves, but that a number of underlying factors affect the length of transport distances, which in turn affect the emissions. A large part of the problem lies in a somewhat inadequate guidance of how to manage excavated soils, which results in limited management possibilities. Ambiguities regarding the current regulations also cause large amounts of excavated soil to be transported long distances instead of being reused on site.To achieve a generality and to examine the applicability in the management of excavated soils, interviews with experts have been conducted. Investigating what the industry believes to be the biggest problems, what should be done, and what the future looks like is important on a topic that covers such a large area.It turns out that the use of a Mass Logistics Centre can to some extent have positive effects on the environment. But what is most important at the present time is to make solid suggestions for changed rules, guidelines and boundaries for the government and the authorities. Then they can more easily publish clear manuals, regulations, and guidelines. Fortunately, these proposals are already underway.

Étude de la valorisation des déblais de chantiers de tunnels en granulats à béton / Study of the use of tunnel excavated materials from Lyon-Turin railway link as aggregates for concrete structures

Colas, Jérémy 04 December 2012 (has links)
La société LTF (Lyon Turin Ferroviaire), filiale de RFF (Réseau Ferré de France) et de RFI (Réseau Ferré Italien) est le promoteur de la section transfrontalière de la future liaison ferroviaire entre Lyon et Turin. LTF souhaite valoriser une grande partie des 16 millions de m3 de déblais qui seront générés par les chantiers du futur tunnel de base en granulats à béton pour le revêtement du tunnel. Cette solution est proposée dans le cadre d'une démarche de développement durable. Cependant, pour une partie des matériaux qui doivent être valorisés en granulats à béton, la teneur en sulfates est comprise entre 1,61 et 4,30% en masse (exprimé en SO3). Ces matériaux se démarquent alors par rapport au contexte réglementaire qui limite la teneur en sulfates dans les granulats à béton à 0,2% pour ce type d'ouvrage. Cette prescription est appliquée pour éviter les risques de dégradation du béton par réaction des sulfates apportés par les granulats avec certains composants présents dans le ciment. Ce phénomène est connu sous le terme de réaction sulfatique interne. Les travaux de recherche ont porté dans un premier temps sur la lixiviation des sulfates issus des matériaux d'excavation. Les résultats ont montré que les sulfates sont rapidement accessibles dans les fractions granulométriques inférieures à 4 mm. Un possible traitement des matériaux par lavage avant leur utilisation dans le béton peut être une solution pour limiter l'attaque sulfatique interne. Dans un second temps, pour définir un liant adapté à ce type de granulats, une étude comparative de différents ciments supposés résistants aux sulfates a été mise en place. Trois essais accélérés ont été développés afin de prendre en compte le risque de dégradation des matériaux cimentaires par formation d'ettringite et de thaumasite. Seuls deux ciments présentent un bon comportement vis-à-vis de la réaction sulfatique interne engendrée par des granulats contenant une forte teneur en sulfates. Il s'agit d'un ciment Portland à très faibles teneur en alcalins et ne contenant quasiment pas d'aluminates tricalciques ainsi qu'un ciment sursulfaté. Enfin, une dernière solution innovante a été proposée et réside dans l'utilisation des sulfates apportés par les matériaux d'excavation pour réaliser le gypsage du ciment. Les sulfates provenant du sable excavé permettent de réguler correctement la prise du matériau cimentaire au même titre que les sulfates de calcium ajoutés au clinker dans le ciment / The construction of a 57 km length base tunnel for the future railway link between Lyon (France) and Turin (Italy) promoted by Lyon Turin Ferroviaire (LTF), subsidiary of Réseau Ferré de France (RFF) and Rete Ferroviaria Italiana (RFI), will result in the production of 16 millions of m3 of excavated materials. In order to promote efficient and sustainable management of natural resources and to reduce greenhouse gas emission and environmental impact, one wish of LTF is to use the most part of these materials as concrete aggregates. However, a part of the excavated materials from LTF tunnel has a sulphate content between 1.46 and 4.30% (expressed in mass of SO3) and cannot be used considering the European standards, which drastically limit the sulphate content in order to avoid structural damages resulting from internal sulphate attack. The sulphate content is limited to 0.2% for this type of construction. The first study, carried out in order to define solutions for the use of these excavated materials, focuses on the behaviour of sulphates, more particularly on their leaching in solution in order to determine the sulphate content that could be released in the concrete. The results show that the sulphates are quickly available for the particles size lower than 4 mm. The washing of excavated materials before their use in concrete can be a solution to limit the internal sulphate attack. The second study has been conducted in order to define a suitable cement for the use of excavated materiels as aggregates. A comparative study of different cements supposed to be resistant to sulphates has been carried out. Three accelerated tests have been developed to assess the risk of degradation of cementitious materials by formation of ettringite and thaumasite. Only two cements show a good behavior against the internal sulphate attack resulting from sulphated aggregates. These cements are a Portland cement with a very low calcium aluminates and alkaline contents and an over sulphated cement.In the frame of a third study, an innovative solution has been proposed and concerns the using of excavated materials as a source of sulphates for regulating the hydration of cement. Sulfates from the excavated sand can regulate the cement hydration and then cancel any further damage due to sulphates


Silva, Marcos Alves da 29 September 2009 (has links)
Made available in DSpace on 2016-08-10T10:31:07Z (GMT). No. of bitstreams: 1 MARCOS ALVES DA SILVA.pdf: 1775464 bytes, checksum: e75c1a592914214c0e8e845737a1ed64 (MD5) Previous issue date: 2009-09-29 / Aquaculture activity, that s a source of protein with low cost, fills your space every day. Thus, there is an increase in water use which has caused major losses of this natural resource, when used irrationally. Soil variables should be studied, as instruments to minimize these losses, encouraging the rational use of these natural resources. This test was conducted in a Yellowish-red clayey Latosol in deep Nursery excavated for aquaculture aimed to evaluate three repetitions of soil permeability (k) and four repetitions of the density (SD) and total soil porosity (TP) under different levels of compression: uncompressed soil (SN), compacted soil with three (CS3), six (CS6) and nine (CS9) footfalls, respectively, of the compactor drum and three footfalls of this compactor on mixture of soil-cement at a rate of 6.6% (SCC). The witness was the native soil removed from the trench 1.5 m deep. Was concluded that the Tukey test (5%), the variables SD and TP showed significant differences between the treatment SN and treatments CS3, CS6, CS9 and SCC was statistically equal the treatment CS3, CS6, CS9 and SCC when compared with each other; for the variable K, showed a significant difference the treatments SN, CS3 and CS6 was statistically equal the treatments CS9 and SCC, considering the cost of treating SCC as a 100%, the treatment CS9 was equivalent to 7% of this cost, demonstrating its economic viability. / A atividade aquícola, por se tratar de uma fonte de proteína de baixo custo, vem ocupando seu espaço a cada dia. Com isso, há um aumento na utilização da água o que tem gerado maiores perdas desse recurso natural, quando usado de forma irracional. Variáveis do solo devem ser estudadas, como instrumentos para minimizar essas perdas, favorecendo o uso racional desses recursos naturais. Esse ensaio foi realizado em um Latossolo Vermelho Amarelo argiloso em fundo de viveiro escavado para a aqüicultura e teve como objetivo avaliar três repetições da permeabilidade do solo (k), e quatro repetições da densidade do solo (DS) e da porosidade total do solo (PT) submetidos a diferentes níveis de compactação: solo sem compactação (SN); solo compactado com três (SC3), seis (SC6) e nove (SC9) passadas, respectivamente, do compactador de percussão e ainda três passadas do compactador de percussão sobre a mistura de solo-cimento na proporção de 6,6% (SCC). A testemunha foi o solo natural retirado em trincheira a 1,5m de profundidade. Conclui-se que pelo teste Tukey (5%), as variáveis DS e PT apresentaram diferença significativa entre o tratamento SN e os tratamentos SC3, SC6, SC9 e SCC sendo estatisticamente iguais os tratamentos SC3, SC6, SC9 e SCC quando comparados entre si; para a variável K, apresentaram diferença significativa os tratamentos SN, SC3 e SC6 sendo estatisticamente iguais os tratamentos SC9 e SCC; considerando o custo do tratamento SCC como 100%, o tratamento SC9 foi equivalente a 7% desse custo, demonstrando sua viabilidade econômica.

Förutsättningar och hinder för att använda offentlig upphandling som styrmedel för en hållbar hantering av entreprenadberg / Public procurement as an instrument for sustainable management of excavated rock

Kleve, Wera January 2014 (has links)
Large volumes of excavated soil and rock are generated in building- and construction projects. These materials need to be transported longer and longer distances due to the densifications of cities. The transportation affects the environment in terms of noise and emissions, but also makes high demands on road infrastructure. To reduce the transport distances an increased responsibility for the excavated rock generated needs to be taken. Responsibility can be increased through an introduction of means of control. Previous studies describe public procurement as an effective tool to increase the responsibility taken by public authorities. Public procurement is regulated by law but the inclusive of environmental requirements is optional, which makes procurement as a tool flexible. The aim of this thesis is to examine public procurement as a tool to control and reduce the environmental impacts from handling, and specifically transporting excavated rock generated in municipal construction projects. The study consists of a case study conducted in Södertörns eight municipalities and a wider analysis that has been carried out in the regions of Stockholm, Västra Götaland and Skåne. The two studies showed that municipal officials generally do not believe that the handling of excavated rock is a municipal responsibility, it lies in the entrepreneurs self-interest to implement regional mass balances. Entrepreneurs instead, consider it to be a municipal problem that can be resolved only when the municipality begins to take responsibility for the excavated rock generated, by example through developing regional plans. As in previous studies, the result indicates that the supplier and purchaser consider the environmental requirements in the procurement process differently. The thesis identify four different factors, which limits the municipalities ability and willingness to take more responsibility in the procurement process regarding the matter excavated rock from construction. These factors are different political position, short term planning, centralization of the procurement units and lack of national and municipal regulations. The study presents that the knowledge in municipal procurement entities is low when it comes to the handling of excavated rock from municipal construction projects. The major knowledge gaps are probably due to the fact that excavated rock for a long time has been seen as an unwanted issue and interest in managing their materials has therefore been low. The knowledge gap must be decreased before the municipalities are able to develop an ethical maturity and take more responsibility in the management of excavated rock. Increased dialogue between different municipal sections and other stakeholders may increase the knowledge. / OptiMass

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